Direct Access to Primary Amines from Alkenes by Selective Metal‐Free Hydroamination
作者:Yi‐Dan Du、Bi‐Hong Chen、Wei Shu
DOI:10.1002/anie.202016679
日期:2021.4.26
selective synthesis of primary aminesfrom easily available precursors is attractive yet challenging. Herein, we report the rapid synthesis of primary aminesfrom alkenes via metal‐free regioselective hydroamination at room temperature. Ammonium carbonate was used as ammonia surrogate for the first time, allowing for efficient conversion of terminal and internal alkenes into linear, α‐branched, and α‐tertiary
bisoxazoline (BOX)/CuII catalyst. This reaction works well with cyclic enol silyl ethers of different sizes, and can be extended to dienol and benzene‐fused substrates, thus providing an effective and general access to a range of 3a‐hydroxy [n.3.0]carbobicycles which are found as a core structure in many natural products. TBDPS=tert‐butyldiphenylsilyl.
新的保险丝:使用新的双恶唑啉(BOX)/ Cu II催化剂实现了标题反应。该反应适用于不同大小的环状烯醇甲硅烷基醚,并且可以扩展至二烯醇和苯稠合的底物,从而提供有效且普遍的接触范围为3a-羟基[ n。3.0]碳双环被发现是许多天然产物的核心结构。TBDPS =叔丁基二苯基甲硅烷基。
Copper-Catalyzed Formal Dehydrogenative Coupling of Carbonyls with Polyfluoroarenes Leading to β-C–H Arylation
作者:Weilong Xie、Dongwook Kim、Sukbok Chang
DOI:10.1021/jacs.0c10904
日期:2020.12.9
We herein communicate a formal dehydrogenativecoupling of carbonyls with polyfluoroarenes enabled by Cu catalysis. Silyl enol ethers initially prepared from carbonyls are postulated to undergo the copper-mediated oxidative dehydrogenativecoupling with polyfluoroarenes via a radicalpathway. Including cyclic and linear ketones, aldehydes, and esters, a broad range of β-aryl carbonyl products were
我们在此交流了通过 Cu 催化实现的羰基与多氟芳烃的正式脱氢偶联。假设最初由羰基化合物制备的甲硅烷基烯醇醚通过自由基途径与多氟芳烃进行铜介导的氧化脱氢偶联。包括环状和线性酮、醛和酯在内,以高区域和立体选择性和优异的官能团耐受性有效地获得了广泛的 β-芳基羰基产物。
Construction of Highly-Functionalized Cyclopentanes from Silyl Enol Ethers and Activated Cyclopropanes by [3+2] Cycloaddition Catalyzed by Triflic Imide
作者:Kiyosei Takasu、Satoshi Nagao、Masataka Ihara
DOI:10.1002/adsc.200600308
日期:2006.11
[3+2] Cycloadditions of silyl enol ethers with donor-acceptor (D-A) cyclopropanes, such as 2-alkoxycyclopropanecarboxylates and 2-(p-methoxyphenyl)cyclopropylphenylketone, proceed in the presence of a catalytic amount of triflic imide (Tf2NH) to give functionalized cyclopentanes in high yield. The catalytic process allows promotion of the cycloaddition of substrates incorporating Lewis basic functions
N-Aminopyridinium salts generate nitrogen-centered radicals by means of photoredox catalysis. Herein, we report that they can be trapped by enol equivalents to give α-amino carbonyl compounds in excellent yields. The broad syntheticutility of this method is demonstrated by functionalization of ketones, aldehydes, esters enol equivalents, vinyl ethers, and 1,3-diketones without the need for prior conversion